Electric heater



. l H' A, ZHOLA ELECTRIC HEATER Filed July 21, 1924 2 sheets-sheet 1 atten/WHA Snug/Lto@ Hefayazwlw elktognew 2 Sheets-Sheet 2 H. A. ZIOLA ELECTRIC HEATER Filed July 2l,l 1924 Patented May 31, 1927.

v UNITED STATES PATENT ori-iceA HENRY A. ZIOLA, OF TOLEDO, OHIO, ASSIGNOB TO THE SWARTZBAUGII MFG. CO., 0F TOLEDO, OHIO, A CORPORATION.

ELECTRIC HEATER -Application illed July 21, 1924. Serial No. 727,861.

Electric heaters of the type involvina concaved reflector member, and centrally sposed heating coil ordinarily involve the employment of a core of suitable insulation inaterial or" substance about which is wound the resistance wire forming the heater member per se. Heretofore there have been used in practically all heaters an insulation core lof a hollow construction, through wlnch a portion of the resistance wire forming the heatin member is passed or looped in the operation of assembling the wire and core Owing to the above method of combining the core and wire elements the assembly l5 operation is a rather ex ensive one because comparatively few of ese heating umts, composed of said two parts, can be assembled by a worker in an honi-s working time.

A primary object of my invention has been the production of a heating unit of the class referred to wherein the resistance wire is arranged unit, no portion thereof running through the center of the core.;` l

A further object of the invention has been 4to provide a core member and the heating unit enabling the resistance wire cils to be wound thereabout in parallel relation, from a point about centrally between the. ends of Y the wire, the terminals being applied in a simplified and advantageous manner to special terminal plates secured to the core. The

arraii ment of said terminal lates is such that tiy may not lonly be readily secured in place upon the core but they are additionally so disposed that a worker may very quickly secure the terminal ends of the resistance wire thereto. These operations are some of the most ex ensive ones vemployed in the ordinary bui driitgr up of a heating unit of the class refer to. Still another feature of my invention has been the formation on the core of the heating .unit of' grooves in which the coiled resistance wire is so seated that there is no liability; of the wire accidentally becoming' laced from the grooves, as byjumpingrom one groove'to another, so as to AresultA ina short circuit or arcing.

Myinvention involves other detailed feawholly upon the outside of thel tures of construction of the unit and arrangement and formation of the resistance wire element which will be more fully apparentupon study oi' the full description in conjunction with the appended drawings in which,

Figure 1 is a side elevation of a reflector electric heater heating unit embodying the invention.

Figure 2 is a vertical sectional view of the same.

Fi re 3 is another side elevational view showing the core member alone.

Figure 4 is a top plan View of the core or insulation member.

Figure 5 is a fragmentary view and elevation bringing out more clearly the way the resistance wire is loo ed at its central portion beneath the hea of a fastening screw, the opposite sides of the wire then being bent in parallelism in the special grooves provided on the outer side of the insulation core.

In the carrying out of my invention I utilize the customarily employed core A which vhowever I have made of a' special construction for the purposes hereinbefore stated. The said core is composed of a relatively large cylindrically shaped hollow body projecting from an integral base member 1.r At opposite sides of the core, ad'acent to the point where the same joins the ase 1, I provide openinvs 2 leading through the wall of the core an establishing communication between po' ts exterior to the core, and theV inner hollow portion 3 thereof. At the outer end of the core, which end is op site to the base 1, I form a recess 4 in w ich is disposed a small screw bolt 5 the screw head of which is adapted to engage and clam there beneath the central portion 6* of the eating element 6 whichis preferably nickel chromium resistance wire. From the recess 4 of the core A there extend parallel ooves :I: and Vy which grooves are forme spirally about the core and extend. in substantially parallel relation to one another, the said grooves terminating, howeverz at opposite sides of the core at the opemngs 2 which have been before referred to.

The heating 'element is coiled substantiall the entire distance from the portion 6a' whic is looped beneath the fastening 5, until it reaches the terminals thereof near the base v1 which terminals are secured by screws 7 standard connector plug to which is attached i the heater cord for connecting the heater with a source of electric current. The'terminal members 9 are screw threaded so as to screw directly into screw threaded openings in the terminal plates 8, and nuts 10 are adapted to be applied to the screw threaded portions of the terminal members 9 so as to clamp the base 1 on one side while the plates 8 are clamped by the parts 9 to the opposite.

side of the base. It will be apparent from the foregoing that very few parts are used in securing the plates 8 to the core and. in holding the terminal members 9 in position on the core so that the operations required for the application of these parts to the core in assembling the heatinr unit, are very few, very simple, and is easily made at the expense of a minimum amount of time and labor.

The grooves a' and y in the surface of the core A arequite deep, in fact almost as deep as the diameter of the coils of the resistance wire heating element 6. Under these conditions, therefore, liability of the jumping of the coils of the heating element from one grooveto another is wholly obviated, and

correspondingly there is no likelihood ofA shortcircuiting or arcing with disadvantageous or even disastrous results.

From the foregoing it will be evident that the application of the heating element 6 to the core A involves simply a wrapping of the ends of the coiled resistance wire in parallel paths around the external surface of the core. It is not necessary as in previous heating units to bring either end of the wire back to the plug terminals through the center of the core.

Another feature of the invention is the provision between the openings 2 in the wall of thecore A of a relatively heavy partition or separating wall 11 that projects from the base 1 a cpnsiderable distance into the hollow portion of the core and forms an effective separating means between the two terminal connections 7 thereby eliminating possibility of short circuiting at these terminals.

By reason of the simplicity of the conwhich its parts may be assembled a very considerably larger number of these units may be made in a predetermined time, than is possible with the more complicated heating unit constructions now commonly found upon the market. Furthermore it is notable that all of the resistance wire which constitutes the heating element is exposed upon the surface of the'core and its heat is thus eiectively neutralized to a maximum degree.

yHaving thus described my invention what I claim as new and desire to secure by Letters Patent, is:

1. As a new article of manufacture, a heating unit for electric stoves comprising a hollow core of refractorysubstance having an integral base at one end, and formed with openings through its wall at approximately the point where the body of the core joins the base, and also formed with a partition integral with the core and with the base and extending from the base some distance into the core, terminal plates disposed at the openings aforesaid, resistance wire wound about the outer surface of the core and connected with said terminal plates and means for securing the terminal plates to the base. f

2. As an article of manufacture, a heating coil for electric reflector stoves com rising a core having a base separated from t e core by a recessed portion, terminal members passing through the base of the core, terminal plates held in place by said terminal members at the recessed portion, a heating coil of resistance wire wound about said core from its outer end toward the base and terminating at opposite sides of the core adjacent the base, and fastenings on the terminal plates securing the resistance wire to said plates at the recessed portion of the core, whereby the resistance Wire Ais wholly xternal to the core and removed from the ase.

3. An electric heating unit for refiecting electric heaters, comprising a hollow insulation core, having a base, spaced terminals passing through the base, the said core being hollow and havinnr opposite openings in its y wall adjacent to the base and leading to its hollow portion, a heating element Wrapped wholly around the outer surface of the core and means connecting terminals of the heating element with said terminal members passing through the base, adjacent to said openings in the core, and comprising terminal plates seated in said openings and having fastenings for attachment of the terminals of the heating element and into which plates the said terminal members are screwed, the terminal plates being external to the core for ready attachment of the heating element terminals.

4. A heating unit for reiecting electric heaters, oomprising a hollow corel having a solid base, and having o enings at opposite sides of the core througlh the wall thereof and said base and the oorebody, L-shapeclI termnal plates in said openings, terminal members pai through the hase and screwed into sai plates, a heating element comprising coiled resistance wire Wrapped about the core from its outer end to the hase, anl fastenings securing the terminals l@ of said heating element to the L-shaped plates.

lin test'mlony Whereo I aix my signa ture.

YNRY A. ZIOLA. 

